A spinal disc lies between endplates of adjacent vertebrae. The disc stabilizes the spine and assists in distributing forces between vertebral bodies. A spinal disc may be displaced or damaged due to trauma, disease or other degenerative processes that can occur over time. For example, a portion of the disk may weaken or tear which can result in the protrusion of the nucleus pulposus into a region of the spine (e.g., the vertebratal foramen) that includes spinal nerves. The protruding nucleus pulposus may press against spinal nerves causing pain, numbness, tingling, diminished strength and/or a loss of motion. Another common degenerative process is the loss of fluid from the disc. Such fluid loss can limit the ability of the disc to absorb stress and may reduce its height, which can lead to further instability of the spine, as well as decreasing mobility and causing pain.
To address the conditions described above, a displaced or damaged spinal disc may be surgically removed from the spine. Historically, after the disc is removed, a fusing implant is inserted into the disc space that allows the two adjacent vertebrae to fuse together. In other surgical procedures, the damaged disc is removed and replaced with an artificial disc. Specialized instruments have been provided to permit access to the disc space and to distract or compress adjacent vertebrae.